Recent works show that amplification and compression of ultrashort fundamental solitons in a gain-distributed nonlinear fiber loop mirror can not only avoid pulse distortion caused by nonlinear effects such as self-phase modulation etc., but also overcome the difficulty of adiabatic amplification that the amplifier length must increase exponentially with the input pulse-width. Weak pulse amplification and compression in the gain-distributed nonlinear fiber loop mirror was investigated. Numerical results show that, as in the cases where the input pulses are fundamental solitons, distortion-free amplification and compression can also be realized when the input pulses have peak powers much lower than those of fundamental solitons, and that the amplified pulses are also close to fundamental solitons. The weaker the input pulse is, the larger the optimum gain of the loop mirror should be, and the higher-order effects have larger influences on the amplified pulses.